Infusion data communication system

ABSTRACT

An infusion data communication system provides a communication link among a fluid container, an infusion pump, and a patient through which identification data may be communicated. Data devices are located at the fluid container and the patient and conduct low frequency RF energy at a low power level containing the data into the medical fluid. The data-laden RF energy propagates through the medication fluid to data readers at the infusion pump which receives the RF energy and reads the data. A comparison is made to verify that the right medication is mounted to the infusion pump for administration to the right patient. RFID devices may be used for the data devices and readers. Pump programming data may also be propagated to the infusion pump from the container RFID tag. The RFID device at the patient may be writable and may be used to store a patient MAR.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims priority to provisional Application No.60/458,311, filed Mar. 28, 2003.

BACKGROUND OF THE INVENTION

The present invention is generally related to fluid infusion, and moreparticularly, to a communication system and method for use inidentification before the delivery of intravenous fluids.

Physicians and other medical personnel apply intravenous (“IV”) infusiontherapy to treat various medical complications in patients. IV infusiontherapy typically involves infusing medical fluids, such as medications,drugs, or nutrients, from a fluid supply or container, such as a bag orbottle, through the tube of a fluid administration set to a cannulainserted into a patient's blood vessel.

In a typical facility, a physician enters an order for medication for aparticular patient. This order may be handled either as a simpleprescription slip, or it may be entered into an automated system, suchas a physician order entry (“POE”) system. The prescription slip or theelectronic prescription from the POE system is routed to the pharmacywhere the order is filled. Typically, the prescribed medication isprepared by a pharmacist and added to a bag or bottle at a pharmacy. Apharmacist also typically identifies the contents of the bag and thepatient for whom the bag is intended with a paper label that is attachedto the bag and in some cases by other means, such as, for example, a barcode or magnetic device, or by use of a radio frequency (“RF”) signalinteractive device such as a radio frequency identification device(“RFID”) tag. The prepared medication is then delivered to a nurse'sstation for administration to the patient.

For safety reasons and in order to achieve optimal results, the medicalfluid is often administered over a period of time in accurate amounts asprescribed by the physician and in a controlled fashion by using aninfusion pump. Infusion pumps operate by displacing the fluid in thetube of a fluid administration set to move fluid from the fluidcontainer through the tube and into the patient. The infusion pump isprogrammed by an operator such as a nurse or other medical personnel,with operating parameters to achieve the administration of themedication as prescribed by the physician. Such operating, or pumping,parameters are medication and patient specific. That is, the pumpingparameters are selected based on the particular medication prescribedand the specific patient for whom they are intended. It is the nurse'sresponsibility to match the prescribed medication with the correctpatient and with the properly programmed pump.

Hospitals and other institutions continually strive to provide qualitypatent care. Medical errors, such as when a patient receives the wrongmedication or receives the correct medication at the wrong time or inthe wrong dosage, are significant problems for all health carefacilities. In the administration of medication, focus is typicallydirected to the following five “rights” or factors: the right patient,the right drug, the right route, the right amount, and the right time.The nurse aims to ensure that these “rights” are accomplished. Systemsand methods seeking to reduce medical errors should also take these five“rights” into consideration.

Medical infusion pumps have advanced greatly over the years and permitmore precise infusion control resulting in much better treatment forpatients. Doctors are more assured that the quantities and rates ofmedication that they prescribe for their patients can be delivered tothe patients accurately by infusion pumps. However, there remains acontinuing concern that the right drug is matched to the right pump, andthat the operating parameters (concentration, schedule, etc.) arecorrectly programmed into the right pump.

In some cases, a single patient may be prescribed multiple simultaneousinfusions of different medications, sometimes four or more, whichrequires multiple infusion pumps that typically are programmeddifferently. In such cases, there will also be multiple administrationsets each with its own fluid conduit or tube to be connected with thepatient. Where there are multiple infusion conduits present, there is aconcern that a fluid conduit may be mounted to the wrong infusion pumpand the associated medication delivered under incorrect pumpingparameters. As an example, where multiple infusion pumps are locatedside by side, or above and below each other, or where a multi-channelpump is used, the multiple fluid sources may be suspended immediatelyabove each pump or pump channel and may become intertwined, thus makingit difficult to select the correct fluid conduit for the particular pumpor channel. Where a more dense infusion pump environment exists, it isimportant to be sure that the correct medical fluid conduits are beingmounted to the correct pump or channel.

Prior attempts have been made to assure that the right medication isadministered to the right patient through the right pump. Patientidentification, medical fluid identification, infusion pumpidentification, and caregiver identification have been achievedelectronically through the use of bar code tags, in some cases RFID(“Radio Frequency IDentification”) tags or devices, and by other means.In these systems, an operator such as a nurse uses a bar code or RFIDreader connected to the pump to read the tags to automatically programthe pump and to verify that the medical fluid identification matches thepatient identification.

Even though the foregoing have provided significant advances in the artto avoid medication errors and have reduced the likelihood of medicationerrors, there still exists some risk that an incorrect fluid containermay become mounted to a pump or pump channel. Stated differently, therestill exists some risk that a fluid container may become connected tothe wrong pump or pump channel. For example, the nurse could possiblyscan the tag of the correct container, but become distracted and mountthe conduit of the administration set connected to the container to thewrong pump channel. Even if the nurse does not become distracted, thevarious fluid conduits in a multiple fluid infusion may be difficult todistinguish from one another and tracing the fluid conduit associatedwith the right container may become burdensome, especially where thefluid conduits have become tangled with each other. In such a case, thenurse may inadvertently choose the wrong fluid conduit to install in thepump even after identifying the correct fluid container.

In one attempt to correctly link the fluid conduit with the right pump,a data bus composed of wires is embedded in or attached to an IV linefor linking a tag reader located adjacent an IV bag's information tag toa data port of a pump unit. However, this system does not provide acommunication path that includes a link between the patientidentification tag and the pump unit to be sure that the bag isconnected to the right patient. It would be advantageous to provide asystem that includes a complete communication path between the patient,the pump, and the fluid container. It would also be advantageous toprovide a system that does not require the use of additional equipmentsuch as wires and connectors that must be assembled together or aseparate tag reader that must be located adjacent an information tag toprovide a communication path. Nurses are quite busy already and addingthe duty of connecting wires together would make their jobs even busier.

Additionally, some record-keeping systems in healthcare facilities donot provide for instantaneous update of a patient's medicationadministration record (“MAR”) when an infusion has been administered.Consequently, there exists the possibility that a healthcare worker maybelieve that the patient has not received his or her infusion and givethe infusion a second time. Therefore, it would also be advantageous toprovide a system that captures infusion information and automaticallyupdates the patient's medication administration record.

Hence, those skilled in the art have recognized that a need still existsfor a system and method to more accurately ensure that the correctfluids are infused into the patient at the correct pumping parameters.In particular, it would be desirable to have a system and method thatprovide for accurate and efficient communication between a medical fluidcontainer, an infusion pump, and a patient for verifying that the rightmedication is delivered to the right patient at the right operatingparameters. A further need has been recognized for a system and methodthat automatically updates the patient's medication administrationrecord. The present invention fulfills these needs and others.

INVENTION SUMMARY

Briefly, and in general terms, the present invention is directed to acommunication system and method for use in the delivery of intravenousfluids. An infusion data communication system having a communicationlink with which relevant administration data may be communicated in amedical fluid administration system is provided, the administrationsystem comprising a medical fluid container at an upstream end, apatient at a downstream end, and a conduit connected to both thecontainer and the patient, through which medical fluid from thecontainer is conducted toward the patient for administration. Theinfusion data communication system comprises a first data transmittingdevice located at either the medical fluid container or the patient, thefirst data transmitting device configured to transmit relevantadministration data into medical fluid residing at its location, theconduit having a lumen containing the medical fluid to be infused to thepatient, and a first data reader device located at the conduit at alocation between the upstream end and the downstream end of the conduit,the first data reader device configured to receive from the medicalfluid in the lumen the relevant administration data transmitted into themedical fluid by the first data transmitting device.

In more detailed aspects, the first data transmitting device is disposedat the medical fluid container and comprises an RFID transponder, andthe first data reader device comprises an RFID reader. Further, thefirst data transmitting device located at the medical fluid container isconfigured to transmit the relevant administration data into the medicalfluid at a frequency and a power level selected such that the data willremain substantially within the lumen of the conduit.

In yet other aspects, the conduit comprises a drip chamber that isconductive to the relevant administration data. Further, the conduit iscoupled downstream to an infusion pump and the first data reader deviceis located at the infusion pump. The relevant administration datacomprises drug identification data, patient identification data, andinfusion parameter data.

In further aspects, the infusion data communication system furthercomprises a second data transmitting device located at the patient, thesecond data transmitting device configured to transmit relevant patientdata into medical fluid residing in the fluid conduit attached to thepatient, and a second data reader device located at the conduit at alocation upstream from the patient, the second data reader deviceconfigured to receive from the medical fluid the relevant patient datatransmitted into the medical fluid by the second data transmittingdevice. The relevant patient data from the second data transmittingdevice comprises patient identification data. Additionally, the conduitis coupled upstream to the infusion pump and the second data readerdevice is located at the infusion pump. A processor compares the patientidentification data from the relevant administration data to the patientidentification data from the relevant patient data and provides an alertif the two patient identification data do not match.

In other more detailed aspects of the invention, the relevant patientdata of the second data transmitting device also comprises a medicaladministration record of the patient. The second data transmittingdevice at the patient comprises an RFID transponder, and the RFIDtransponder at the patient is writable. Additionally, the second datareader device located upstream of the patient comprises a second RFIDreader which is configured to also transmit patient medicationadministration record data into the fluid in the lumen of the tube. Theprocessor is configured to transmit with the second data reader/writerdevice data regarding the current administration of medication into themedical fluid in the lumen, the second data transmitting device beingalso writable and being configured to receive the current administrationdata from the medical fluid and write such received data into the seconddata transmitting device at the patient.

These and other advantages of the invention will become apparent fromthe following more detailed description when taken in conjunction withthe accompanying drawings of illustrative embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a medical administration system having fourfluid infusion pumps, each of which is connected to a respective fluidcontainer for pumping the contents of the fluid container to a patient,the fluid containers being mounted on a common roller stand;

FIG. 2 is an enlarged view of a portion of the medical administrationsystem of FIG. 1 showing two of the fluid infusion pumps mounted ateither side of a programming module, and the displays and control keysof each, with the programming module being capable of programming bothinfusion pumps;

FIG. 3 is a perspective view of one of the fluid infusion pumps of FIGS.1 and 2 with its front door in the open position showing two RFIDreaders used in accordance with aspects of the present invention, aperistaltic four finger pump mechanism, and a fluid conduit in operativeengagement with the infusion pump;

FIG. 4 is a schematic view of a communication system in accordance withaspects of the present invention, including the two infusion pumps fromFIG. 2 operatively connected to medical fluid containers and to apatient for delivery of medical fluid and showing the communicationpaths used for communication between the medical fluid containers,infusion pumps, and patient;

FIG. 5 is a more detailed view of one of the communication pathsdepicted in FIG. 4, showing the transmission of RF signals between thedata device mounted to a medical fluid container and the data readermounted to an infusion pump, including capacitive coupling through thecontainer wall and the conduit wall; and

FIG. 6 shows a block diagram of the components of one of the infusionpumps from FIGS. 1 and 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In accordance with aspects of the invention, there is provided a uniquecommunication system and method that automatically ensure that theproper medication and dosage are delivered to the patient for whom thatmedication and dosage are intended. An information communication networkis provided that uses the IV fluid and the patient's body as carriers oflow power radio frequency (“RF”) signals. The infusion pump receivesthese signals from the IV fluid allowing identification of the patientand the medical fluid container and in some cases allows pumpprogramming to be automatically accomplished, thus reducing the numberof manual operations required of the caregiver.

Referring now in more detail to the drawings in which like referencenumerals refer to like or corresponding elements among the severalviews, there is shown in FIG. 1 a medical administration system 20having four medical administration devices 22, 24, 26, and 28, which areinfusion pumps in this embodiment, each of which is in operativeengagement with a respective fluid administration set 30, 32, 34, and36. Medical fluid supplies or containers 38, 40, 42, and 44, which maytake various forms but in this case are shown as inverted bottles, aresuspended above the pumps. Fluid supplies may also take the form of bagsor other types of containers. Both the infusion pumps 22, 24, 26 and 28and the fluid containers 38, 40, 42, and 44 are mounted to a rollerstand or IV pole 46.

Each administration set 30, 32, 34, and 36 is connected between arespective fluid container 38, 40, 42, and 44 and the same patient 48 sothat the patient may receive the fluids in all four fluid containers. Aseparate infusion pump 22, 24, 26, and 28 is used to infuse each of thefluids of the fluid containers into the patient. The infusion pumps areflow control devices that will act on the respective tube or fluidconduit of the fluid administration set to move the fluid from the fluidcontainer through the conduit to the patient. Because individual pumpsare used, each can be individually set to the pumping or operatingparameters required for infusing the particular medical fluid from therespective fluid container into the patient at the particular rateprescribed for that fluid by the physician. Such medical fluids maycomprise medications, drugs, nutrients, or other therapeutic fluids aspreviously mentioned.

Typically, medical fluid administration sets have more parts than thoseshown in FIG. 1. Many have check valves, drip chambers, valved ports,connectors, and other devices well known to those skilled in the art.Except for FIG. 4 where a drip chamber is shown as part of theadministration set, these other devices have not been included in thedrawings so as to preserve clarity of illustration. However, thoseskilled in the art will understand that the inclusion of such otherdevices may often occur.

In accordance with the background discussed above, it is desirable toverify that each fluid container 38, 40, 42 and 44 is associated withthe correct patient 48, that the pumping parameters for a given medicalfluid have been correctly programmed into the infusion pump 22, 24, 26or 28, and that each fluid container is correctly connected to theappropriately programmed pump. As will be discussed in more detailbelow, the present invention provides a communication link between thepatient and each pump, and between each medical fluid container and eachpump. Using these communication links, data devices associated with themedical fluid containers, such as data transmitting devices 49, 50 51,and 52 shown mounted on the bottles, or a data transmitting device 92(shown in FIG. 4) associated with the patient 48, may communicaterelevant administration data to the pumps for verifying that the medicaladministration system 20 has been connected correctly. Relevantadministration data may include various data related to theadministration of medical fluid to a particular patient. For example,relevant administration data may include drug identification, patientidentification, and other information believed to be relevant.

It should be noted that the drawing of FIG. 1 is not to scale and thatdistances have been compressed and sizes have been exaggerated for thepurpose of clarity. In an actual setting, the distance between thecontainers 38, 40, 42, and 44 and the infusion pump 22, 24, 26, and 28could be much greater. There would be more of an opportunity for thetubes of the administration sets 30, 32, 34, and 36 to becomeintertwined with each other when all four are dangling from thecontainers, which can cause confusion as to which tube should be inwhich infusion pump. The opportunity for confusion increases as thenumber of tubes increases. However, it should also be understood thatthe present invention is also useful in cases where a single pump andsingle medical fluid container are involved, as the system may also beused to confirm that the correct medication has arrived for the patientand that the infusion parameters have been correctly programmed into thepump.

Referring now to FIG. 2, an enlarged view of the front of the infusionpump 24 is shown. The pump includes a front door 53 and a handle 54 thatoperates to lock the door in a closed position for operation and tounlock and open the door for access to the internal pumping and sensingmechanisms and to load administration sets for the pump. When the dooris open, the tube can be connected with the pump, as will be shown inFIG. 3. When the door is closed, the tube is brought into operatingengagement with the pumping mechanism and the other equipment of thepump. A display 55, such as an LED display, is located in plain view onthe door in this embodiment and may be used to visually communicatevarious information relevant to the pump, such as alert indications(e.g., alarm messages). Control keys 56 exist for programming andcontrolling operations of the infusion pump as desired. The infusionpump 24 also includes audio alarm equipment in the form of a speaker 58(shown in FIG. 5).

In the embodiment shown in FIG. 2, the infusion pump 24 is attached tothe right side a programming module 60. Other devices or modules,including another infusion pump, may be attached to the right side ofthe infusion pump 24, as shown in FIG. 1. In such a system, eachattached pump represents a pump channel of the overall medicaladministration system 20. In one embodiment, the programming module isused to provide an interface between the infusion pump 24 and externaldevices as well as to provide most of the operator interface for theinfusion pump 24. Attention is directed to U.S. Pat. No. 5,713,856entitled “Modular Patient Care System” to Eggers et al., incorporatedherein by reference, in which the programming module is described as anadvanced interface unit. In other cases, the programming module isreferred to as a “point-of-care unit.”

The programming module 60 includes a display 62 for visuallycommunicating various information, such as the operating parameters ofthe pump 24 and alert indications and alarm messages. The programmingmodule 60 may also include a speaker (not shown) to provide audiblealarms. The programming module also has various input devices in thisembodiment, including control keys 64. The programming module also has acommunications system (not shown) with which it may communicate withexternal equipment such as a medical facility server or other computerand with a portable processor, such as a handheld portable digitalassistant (“PDA”), or a laptop-type of computer, or other informationdevice that a caregiver may have to transfer information as well as todownload drug or medication libraries to a programming module or pump.The communications system may take the form of a RF system, an opticalsystem such as infrared, a Blue Tooth system, or other wired or wirelesssystem. The communications system may alternatively be includedintegrally with an infusion pump, such as in cases where it is a standalone pump. Further, information input devices need not be hard-wired tomedical instruments, information may be transferred through a wirelessconnection as well.

FIG. 2 includes a second pump module 26 connected to the programmingmodule 60. As shown in FIG. 1, more pump modules may be connected.Additionally, other types of modules may be connected to the pumpmodules or to the programming module.

Turning now to FIG. 3, the infusion pump 24 is shown in perspective viewwith the front door 53 open, showing the administration set 32 inoperative engagement with the pump 24. The fluid administration set 32comprises a fluid conduit or tube 66, extending from the respectivefluid container 40 (FIG. 1) to the patient 48, upon which the pump actsto move fluid downstream to the patient. Specifically, a pumpingmechanism 70 acts as the flow control device of the pump to move fluidthough the conduit. In this case, the pumping mechanism is of the “fourfinger” type and includes an upstream occluding finger 72, a primarypumping finger 74, a downstream occluding finger 76, and a secondarypumping finger 78. The “four finger” pumping mechanism and mechanismsused in other linear peristaltic pumps operate by sequentially pressingon a segment of the fluid conduit by means of the cam-following pumpingfingers and valve fingers 72, 74, 76, and 78. The pressure is applied insequential locations of the conduit, beginning at the upstream end ofthe pumping mechanism and working toward the downstream end. At leastone finger is always pressing hard enough to occlude the conduit. As apractical matter, one finger does not retract from occluding the tubinguntil the next one in sequence has already occluded the tubing; thus atno time is there a direct fluid path from the fluid container to thepatient. The operation of peristaltic pumps including four finger pumpsis well known to those skilled in the art and no further operationaldetails are provided here.

In this particular embodiment, the pump 24 also includes two data readerdevices, upstream data reader device 80, and downstream data readerdevice 82, for receiving information relating to the infusions, such asdrug identification, patient identification, and optionally otherinformation such as nurse identification. The data reader devices maycomprise RFID readers (or receivers) or other wireless devices that arecompatible with the data transmitting devices 50 and 52 associated withthe fluid containers 40 and 42 and the data transmitting deviceassociated with the patient. Although referred to as data reader devicesor RFID readers or receivers, the data reader devices may also transmitinterrogation signals to the RFID transponder associated with the fluidcontainer or the patient and as described below may also transmit datainto the medical fluid in the tube lumen. Likewise, although referred toas data transmitting devices or RFID tags or RFID transponders, datatransmitting devices may also receive or read data and may also rewritable, as is discussed below in more detail. The readers 80 and 82are operatively connected to the infusion pump and, in this embodiment,are further provided as an integral part of the pump 24. While thereaders 80 and 82 may be located at a different location in the pumpthan shown in FIG. 3 or may even be a separate component in operativeconnection with the pump, the upstream data reader device 80 isgenerally located upstream from the pumping mechanism 70, that is, at alocation between the fluid container 40 (FIG. 1) and the pumpingmechanism. Likewise, the downstream data reader device 82 is generallylocated at a downstream location with respect to the pumping mechanism,i.e., between the pumping mechanism and the patient 48. In anotherembodiment, the pump 24 may include a single data device, either theupstream data reader device 80 or the downstream data reader device 82.

The terms “upstream” and “downstream” as shown in FIG. 1 and as usedherein in various places is meant to provide an indication of relativepositioning as well as indicate the positions of certain specificdevices. For example, the patient is located “downstream” from the pumpand is also “downstream” from the container. The pump is located“upstream” from the patient, as is the container. On the other hand,there is an “upstream data reader device” and a “downstream data readerdevice” which denote their relative positions on the pump.

As mentioned above, once the tubing 66 is engaged with the pumpingmechanism 70 and the door 53 of the pump is closed, the pumpingmechanism always provides an occlusion of the channel so that there isnever an open fluid line from upstream of the pumping mechanism todownstream of the pumping mechanism. At the location of such anocclusion, any medical fluid carried by the tube is absent and thereforecannot provide a conductive path for energy introduced into the medicalfluid by a data transmitting device 50 and 92, such as an RFID tag. Thisprevents low frequency RF signals that are being transmitted though thefluid in accordance with an aspect of the invention from travelingacross the entire pumping mechanism. Thus, providing one reader upstream80 and one reader downstream 82 from the pumping mechanism permitscommunication with signals from both segments of the fluid line.

The occlusion of the fluid line 66 provided by the pumping mechanism 70is advantageous in that it reduces the opportunity for cross-talkbetween fluid container data via a common patient-side conductive path.It is not uncommon for a single pumping system to have multiple channelsthat are connected to the same patient. In such cases, it may beundesirable for data from one medical fluid container channel to becommunicated to another channel due to the common connection with thesame patient. Although other steps may be taken due to the design ofRFID devices themselves to prevent cross-talk interference, such astheir anti-collision logic systems, the occluding devices in aperistaltic pump can effectively interrupt the communication of lowfrequency RF signals from the fluid container to the patient, therebyadding even more to resistance against cross-talk.

In another embodiment, as mentioned above, there may be a single datareader device located at the pump 24 that is used to read both the datatransmitting device 50 at the medical fluid container and the datatransmitting device 92 at the patient 48. This may be useful in the casewhere only a single conduit is used to infuse medical fluid to thepatient. In such case, there are no multiple fluid conduits connected tothe same patient through which crosstalk may occur.

FIG. 4 depicts a schematic view of the medical administration system 20discussed above and an infusion data communication system in accordancewith one embodiment of the present invention. An upstream communicationpath 84 is provided through the upstream portion 86 of the fluid conduit66 which interconnects the fluid container 40 with the pump 24. Moreparticularly, the upstream communication path 84 is provided via themedical fluid being moved from the container 40 through the conduit 66.A downstream communication path 88 is provided through the downstreamportion 90 of the conduit 66 which interconnects the pump 24 with thepatient 48, also via the medical fluid in the conduit 66. Forillustrative purposes, the communication paths 84 and 88 between theinfusion pump 24 and the medical fluid container 40 and the patient 48are shown as arrows in FIG. 4. Such communication paths may be providedfor each fluid line associated with the patient 48. Although the arrowsare shown on either side of the fluid conduit 66 in FIG. 4 for clarityof illustration, it should be understood that the communication pathsare actually provided through the fluid conduit 66 via the medicalfluid.

The upstream communication path 84 links the data transmitting device 50associated with the medical fluid container 40 to the upstream datareader device 80 of the pump 24, and the downstream communication path88 links the data transmitting device 92 associated with the patient 48to the downstream data reader device 82 of the pump 24.

In embodiments where the data reader devices 80 and 82 are RFID readers,the data transmitting 80 and 82 may comprise RFID transponders. In oneembodiment, the relevant patient data transmitting device 92 is apatient information transmitter that may comprise an RFID tag that canalso record information (i.e., is writable). The relevant patient datastored and transmitted by the RFID transponder 92 may include variousinformation, for example, the patient's name, hospital identificationnumber, and other information such as the patient's age, weight,condition, and allergies. In another embodiment, the patient's RFIDtransponder may also contain the patient's MAR (medicationadministration record) which the pump can update by writing informationinto its stored MAR data. Similarly, the fluid container RFIDtransponder 50 is a fluid identification transmitter that may alsocomprise an RFID tag. The container's RFID transponder 50 typicallystores and transmits relevant administration data including patientidentifiers such as numeric and alpha (name), a drug identifier, a drugconcentration, a diluent fluid identifier, a dose or flow rate, otherpumping-related parameters, and contra-indicated medications/conditions.

In one embodiment, the communication system of the present inventionuses low power, low frequency RF signals for transmitting data via thecommunication paths 84 and 88. For example, the RF signals may have afrequency of about 100-300 kHz and a power of less than 100 nanowatts inthis embodiment. It has been found that frequencies and power of thisnature are conducted well enough by the ionic medical fluids yet areconducted poorly, if at all, by the material forming the wall of conduit66 and air outside the conduit. These frequencies are not low enough tocause a muscle reaction in patients and are not high enough to radiatethrough tubing and through the ambient air. As a result, thecommunication energy used in the communication system in accordance withthe invention is substantially confined by the wall of the tube 66.However, energy of other frequencies and power levels may function wellalso. Therefore, conduits that touch each other will not pass the databeing conducted within the conduit to the touching conduit.

The transponders 50 and 92 may automatically and periodically transmittheir information via the communication paths using the low frequency RFsignals. The transponders 50 and 92 may be self powered or powered by aninterrogation signal from an RFID reader 80 or 82 on the pump 24. Asshown in FIG. 4 in exaggerated form, the transponders may each includean antenna 94 for receiving interrogation signals from a reader.

In one embodiment, the patient RFID transponder 92, which takes the formof a wristband in FIG. 4, is coupled to the downstream communicationpath 88 and to the RFID reader 82 via a further communication pathwaythrough the patient 48. The RFID transponder 92 attached to the patient48 may transmit the RF signals through the patient's body and throughthe medical fluid residing in the fluid conduit 66 attached to thepatient, thereby providing communication with a medical administrationdevice not directly attached to the body. The transmission of low rangeRF signals through the patient's body and through the fluid in the fluidconduit 66 provides a discrete communication path which avoidsinterference with the RF readers in adjacent pump channels.

When the fluid conduit 66 is mounted to the pump 24, the RFID readers 80and 82 are placed into data communication with respective RFIDtransponders 50 and 92 via the communication paths 84 and 88 and receivesignals being transmitted through the medical fluid residing in therespective conduit portions 86 and 90. FIG. 5 illustrates thetransmission of RF signals along the upstream communication path 84. RFsignals are transmitted into the medical fluid by the two RFIDtransponders 50 and 92. They propagate through the medical fluid intheir respective fluid segments due to the ionic nature of that fluid.Those in the upstream portion 86 may be detected by the upstream reader80 at the pump via capacitive coupling through the conduit wall 102, asshown in FIG. 5. RF signals in the downstream communication path 90 maysimilarly be transmitted through the conduit wall to the downstreamreader 82.

In one embodiment, the pump 24 includes an electrically conductivedevice, such as metallized half-pipe 104, which is coupled to the RFIDreader 80 to improve capacitive coupling through the conduit wall 102.The administration set 32 may also contain conductive devices to providemore efficient coupling with the pump's RFID readers. For example, aconductive device may be located in a fitment of the administration set32 and may be configured to be mounted to a counterpart device in thepump 24, such as a half-pipe 104. For example, the conduit 66 mayinclude a metallized or ceramic cylindrical insert that will be locatedadjacent the respective RFID reader 80 or 82 when the conduit 66 isproperly loaded in the pump 24.

Similarly, the RFID transponder 50 mounted to the medical fluidcontainer 40 is located and configured such that it may conduct RFsignals to the fluid within the container via capacitive couplingthrough the container wall 100 in a way similar to that described above.The fluid container 40 may be fabricated to optimize the coupling of lowfrequency RF currents from the reader 50 into the medical fluid.

In another embodiment, fluid tubing formed of a more electricallyconductive substance may facilitate the coupling between the RFIDreaders of the pump and the RFID transponders of the fluid container andpatient, or may itself provide a suitable data signal conductingpathway. Other devices that may form a part of the administration set,such as a drip chamber 106 shown in FIG. 4, may also be formed of RFconductive material to improve the transmission of signals through thefluid line, particularly if the device may interrupt the fluid streamwithin the conduit. Such an interruption in the fluid pathway may bebridged by manufacturing the drip chamber from materials that are ableto conduct the RF currents from the drip orifice at the upstream end ofthe drip chamber to the fluid in the drip chamber body. The improved RFconductivity may be provided by coatings and/or the embedding ofconductive materials, such as carbon, within the drip chamber materialor other molded component. Alternatively, a fiber material may be coatedon the interior surface of the drip chamber to enable the medical fluidto maintain a fluid pathway through the drip chamber through a wickingeffect.

Referring now to FIG. 6, the infusion pump's 24 RFID reader 80, whichincludes a decoder, converts the RF signals received from the fluidcontainer transponder 50 (FIG. 4) into digital form. Similarly, thedownstream reader 82 receives signals from the patient transponder 92(FIG. 4) and converts them into digital form. The pump 24 includes amemory 110 for storing the received data and a processor 112 configuredto analyze the data. Alternatively, the processor and the memory may beassociated with the programming module 60 (FIG. 2) rather than the pump24 in cases where a modular system is used. In another embodiment, theprocessor 112 and memory 110 may be located in a separate computer orworkstation from the pump or programming module, or may even be locatedin a remote computer or server in communication with the pump orprogramming module via a wired or wireless network. As will berecognized by one skilled in the art, other arrangements are alsopossible.

In one embodiment, the processor 112 is configured to analyze the datareceived from the fluid container transponder 50 to determine if thecorrect fluid conduit has been loaded into the pump. For example, aftera caregiver programs a pump by entering information such as drugidentification and infusion parameters, the processor 112 may comparethe entered drug identification with the drug identification transmittedby the fluid container transponder 50. If the drug identifications donot match, the processor 112 may activate an alarm to notify thecaregiver of the discrepancy and will not permit the pump to begin theinfusion until a response to the alarm has been received. The processor112 may additionally check the entered infusion parameters with thosetransmitted by the fluid container transponder 50 to verify that thisdata matches as well. In the case of a modular infusion pump system,such as that shown in FIG. 1, where there is a single programming unit60 that is used with multiple attached infusion pump modules 22, 24, 26,and 28, the programming unit 60 is used to program each of the infusionpump modules. The infusion pump modules may also be thought of asinfusion “channels.” The system and method in accordance with theinvention is particularly useful in such a modular infusion system inthat each infusion channel will have its own set of reader devices 80and 82 (see FIG. 3). As the tube 66 for each container is installed ineach infusion channel, the respective readers of that channel receivethe data from the container attached to that tube. The programming unitwill then receive the data from the channel and will compare that datato the programming instructions for that channel. If there is adiscrepancy, the programming unit 60 will present an alarm.

As an example, if the programming unit 60 were used to program theinfusion pump module 26 that is the second from the left in FIG. 1,“channel B,” to infuse Dopamine, but the data from the upstream datareader 80 (FIG. 3) of channel B shows that the container attached tothat tube contains Dextrose, the programming unit would provide an alertto the operator that the medication in channel B is incorrect. Theprogramming unit would then not permit channel B to begin infusion untilthe discrepancy has been remedied. Further, if another channel attachedto the programming unit, for example channel D (numeral 22), wereprogrammed to administer Dextrose, the programming unit may also displaythe information that the tube that has been installed in channel Bshould instead be installed in channel D.

The processor 112 may also analyze the data by comparing the data fromthe patient transponder 92 to the data received from the fluid containertransponder 50. The processor 112 verifies that the patientidentification data received from the two sources matches to ensure thatthe correct medication is attached for the correct patient, and warnsthe caregiver through the operator interface of the infusion pump orother related device of any mismatch. Further, the infusion pump willnot deliver fluid if a mismatch is detected. In the case of a mismatch,the processor may display an alert indication visually on the display 55of the infusion pump 24 and/or an audible alarm from the speaker 58 ofthe pump (FIG. 2). The alert indication may also be provided on thedisplay 62 and/or speaker of the programming module 60 (FIG. 2). In someembodiments, a record of the alert, together with related infusion data,may be stored in the memory 110 and/or communicated to a workstation,such as a nurse's station, the pharmacy, or a remote computer or server.In such cases, the record is available for further analysis and reportgeneration.

If the wrong conduit 66 has been placed in the pump 24, the caregivermay reload the pump and attempt to program the pump again, with theverification process occurring again automatically. If the pump verifiesthat the patient identification data and fluid container transponders 92and 50 match, a verification indication may be displayed on the displays55 or 62 (FIG. 2) and the pump may permit the caregiver to continueprogramming the pump and/or begin the infusion. After programming of thepump is completed, the processor 112 will control the flow controldevice or pumping mechanism 70 to begin the infusion and move fluidthrough the fluid conduit 66 to the patient 48.

In one embodiment, the data transmitted from the fluid containertransponder 50 may be used to automatically program the pump 24. Thetransmitted data, which may be stored in the memory 110 and accessed bythe processor 112, may include the drug name and concentration, as wellas various infusion parameters for the pump 24, such as dose or flowrate. The transmission of the fluid container data along the discretecommunication path 84 ensures that the pump is receiving data associatedwith the fluid supply that is actually connected to the pump, therebyavoiding inadvertent loading of a different conduit in the pump. Oncethe medical fluid has been matched to the patient and the operatingparameters have been transferred from the fluid container transponder 50to the infusion pump, the caregiver may be prompted by the infusion pumpto confirm the programmed data, including patient identification.

In one embodiment, the pump 24 may contain a drug library, whichgenerally includes institutionally-established guidelines foradministration of various medical fluids. For example, the drug librarymay include institutionally-established guidelines or limits on drugadministration parameters, such as dosage, frequency of administration,and other delivery related information such as, for example, appropriateflow rates and infusion durations for programming infusion pumps. Thedrug library may be stored in the memory 110 of the pump 24 or in amemory of the programming module 60 (FIG. 2) or another memory connectedto the pump 24 via a wired or wireless network. Other library storagearrangements are possible. Before the pump 24 is allowed to infuse amedical fluid into a patient, the processor 112 may be configured tocheck the operating parameters of the pump 24 against the drug library.

The drug library may contain “hard” and “soft” limit values on dosingparameters and other infusion parameters. Once the operating parametershave been programmed into the pump 24, the processor 112, according toits programming, will enter a verification stage in which it comparesthe programmed values against the stored library to verify that theprogrammed values are within acceptable ranges. If a programmed valuecontravenes a hard limit, the processor 112 may activate an alarm andrequire a value change before operation of the pump 24 can begin. If theprogrammed value contravenes a soft limit, the processor 112 may requirean acknowledgment from the caregiver that he or she understands that thevalue entered is outside a soft limit but that this value isnevertheless to be used.

The drug library of the medical administration system may be configuredto be periodically updated through the communications system using anexternal device such as a computer running appropriate software.Alternatively, the drug library may be stored on a remote computer orserver in communication with the pump or programming module via a wiredor wireless network.

The drug library may also include guidelines associated withpatient-specific information that may be provided by the patient RFIDtransponder 92 attached to the patient 48. For example, in addition tostoring patient identification data, the patient RFID transponder 92 mayinclude patient characteristics, such as the patient's age, weight,medical conditions, allergies, and other known medical information.Information regarding the patient's medical history may also be storedin the patient RFID transponder 92. In one embodiment, the patient RFIDtransponder 92 contains the patient's MAR. These patient characteristicsmay be transmitted to the infusion pump 24 for comparison with theguidelines of the drug library in order to increase the safety andefficacy of the infusion program. In particular, the drug library maycontain guidelines or limits for the administration of certain medicalfluids based on particular patient characteristics, such as allergies,weight, age, medical condition, and other data.

In embodiments where the patient's MAR is stored in the patient RFIDtransponder 92, the processor 112 of the infusion pump 24 may beconfigured to check the patient's MAR stored on the RFID transponder 92for any allergies of the patient, for other drug treatments (such asprior or concurrently scheduled infusions) that may provide acontra-indication to the present infusion, and for othermedically-significant information. In one embodiment, the processor 112of the infusion pump 24, or a processor of another monitor or module incommunication with the infusion pump 24, may be programmed to read thepatient's RFID transponder 92 and present that information on a display.For example, the pump 24 may contain a “patient MAR monitor” mode inwhich the contents of the patient's MAR retrieved from the patienttransponder 92 may be displayed on display 55 or 62 (FIG. 2) and may bequeried for certain information.

If the patient transponder 92 is a writable device, such as a writableRFID tag, the infusion pump 24 may additionally write information aboutthe present infusion into the patient's MAR stored on the transponder92. The transponder 92 attached to patient 48 may accordingly containup-to-date information in the MAR to further ensure proper treatment atthe hospital. For example, where the drug library resident in the pumpincludes guidelines for certain infusions based on other prior orconcurrent infusions, the patient transponder 92 may provide the pump 24with the patient's updated medical history for comparison with theguidelines. In accordance with healthcare facility procedures, the MARin the patient's RFID transponder 92 may also be coupled to a healthcarefacility server through other communication means, such as, for example,a wired or wireless network or a combination of wired and wirelesscommunication channels, so that there is a backup copy of the MAR.

One particular mode of operation of the present invention will now bedescribed. A patient 48 entering a hospital or other care-givingfacility is provided with a wristband, necklace, ankle band or otheridentifier that is affixed to the patient in a manner so that thepatient can be identified even if the patient is unconscious orotherwise unresponsive. This wristband or other device may include adata transmitting device, such as an RFID transponder 92, containingdata representing the patient's name, hospital identification number,and other information that the facility has determined is important.Additional information such as the patient's age, weight, condition,allergies, and other known medical information may also be programmedinto the device. In one embodiment, the patient's MAR is also programmedinto the transponder. Periodically, the transponder will transmit thisinformation through the patient's body using extremely low amplitude,low frequency, RF currents. In one embodiment as stated above, the RFsignals have a frequency of about 100-300 kHz and a power of less than100 nanowatts.

After the patient is admitted and situated in a bed within the facility,the patient is typically evaluated by a physician and a course oftreatment is prescribed. The physician prescribes a course of treatmentby preparing an order which may request a series of laboratory tests oradministration of a particular medication to the patient. In some cases,the physician prepares the order by filling in a form or writing theorder on a slip of paper to be entered into the hospital system forproviding care. In other cases, the physician may enter the medicationorder directly into a physician order entry system or may instruct anurse or other care-giving professional to do so.

If the order is for administration of a particular medication regimen,the order will be transmitted to the facility's pharmacy. The order willarrive in written or electronic form at the pharmacy, will be evaluatedby the pharmacy, and processed. The pharmacy then prepares themedication according to the requirements of the physician. Typically,the pharmacy packages the medication in a container, and a copy of theorder, or at a minimum the patient's name, the drug name, and theappropriate treatment parameters are represented on an RFID transponder50 or other data transmitting device that is affixed to the drugcontainer.

However, in cases where the prescription is processed and/or prepared atthe nurse's station rather than the pharmacy, the prescription RFID tagwould be prepared at the nurse's station. If it is not already affixedto the medical container, the nurse would attach it to the fluidcontainer received from the pharmacy or prepared by the nurse. In suchcases, the fluid container may include two RFID tags, a first RFID tagfrom the pharmacy for identifying the drug and concentration and asecond prescription RFID tag created at the nurse's station foridentifying the patient, the drug prescribed, relevant infusionparameters, the physician's name, and any other relevant informationdesired. In another embodiment, the first RFID tag from the pharmacy maybe a writable tag, in which case a nurse may program the additionalprescription information on to that tag when preparing the prescription.If the prescription RFID tag is prepared at the nurse's station inresponse to a physician's verbal orders, for example, that tag wouldalso include the nurse's name, badge number, and information concerningthe physician and the physician's verbal orders.

Generally, the medication is then delivered to the appropriatecare-giving unit for administering to the patient. A nurse or techniciancarries the medical fluid container 40 to the appropriate patient 48.The nurse begins by hanging the container 40 of medical fluid from astand, such as the roller stand 46 shown in FIG. 1, priming the conduit66 of a fluid administration set 32 with the fluid from the fluidcontainer 40 to be infused into the patient 48, and loading the conduit66 into the pump 24. The transponder 50 for the medical fluid container40 transmits RFID signals through the conduit 66 via the fluid, and thesignals are received by RFID reader 80 at the upstream end of theinfusion pump 24. The received signals may represent informationincluding infusion parameters that may be used to program the pump 24automatically. This information may also be displayed on displays 55 or62 (FIG. 2).

At the bedside, a vascular access device (“VAD”) is typically placed inthe patient's vascular system or body space (epidural, intrathecal,subarachnoid, etc.). Once the VAD has been connected to the primedadministration set 32, the RFID signals from the patient transponder 92travel through the medical fluid in the conduit 66 and are detected bythe RFID reader 82 at the downstream end of the infusion pump 24. Thedata transmitted from both the fluid container transponder 50 and thepatient transponder 92 are compared to verify whether the patientidentification data matches. In case of a mismatch, the pump 24 alertsthe caregiver and prevents fluid delivery fluid from commencing. If thepatient identification data matches, the correct connection of the fluidcontainer 40 to the patient 48 has been verified. The system thusprovides for relatively automatic identification and processing todetermine if the right drug is being administered to the right patient.

In addition, patient characteristics and/or the patient's MAR may alsobe stored in and transmitted by the patient transponder 92. The medicaladministration system 20 may include a drug library having medicationadministration guidelines including protocols and limits providingranges of acceptable values for infusion parameters. Such guidelines mayutilize the patient characteristics received from the patienttransponder 92. If the system detects an out-of-range value for aparameter, the pump provides an appropriate alert to the caregiver.

Once the infusion pump 24 or other medical administration device isconfigured, the nurse, caregiver, or technician starts the infusion bypressing the appropriate control on the infusion pump 24 (FIG. 4). Inembodiments where the patient transponder is writable, information aboutthe infusion may then be transmitted from the pump 24 and written ontothe patient transponder 92 to provide an updated MAR.

From the foregoing, it will be appreciated that the system and method inaccordance with the principles of the invention provide effective meansto verify that a fluid container is correctly connected to an infusionpump in order to ensure infusion of the proper drug to the patient. Theinterconnection between the fluid container and the infusion pump, andbetween the patient and the infusion pump, results in a completecommunication system designed to further reduce the occurrence ofmedication errors and provide further patient safety as well as make theinfusion process easier and more efficient for healthcare workers.

In the above detailed description, well-known devices, methods,procedures, and individual components have not been described in detailso as not to obscure aspects of the present invention. Those skilled inthe art will understand those devices, methods, procedures, andindividual components without further details being provided here.Moreover, while the embodiments disclosed above are described for use ina hospital environment, it will be understood that the system and methodmay be useful in other environments as well, such as outpatient clinicsand other environments where care is delivered to a patient.

While several specific embodiments of the invention have beenillustrated and described, it will be apparent that variousmodifications can be made without departing from the spirit and scope ofthe invention. Accordingly, it is not intended that the invention belimited, except as by the appended claims.

1. An infusion data communication system having a communication linkwith which relevant administration data may be communicated in a medicalfluid administration system, the administration system having a medicalfluid container in which is located medical fluid for administration toa patient and a conduit with a lumen through which the medical fluidfrom the container is conducted to the patient for administration, theadministration system having an upstream end at which the container islocated and a downstream end at which the patient is located, theinfusion data communication system comprising: a first data transmittingdevice located at either the upstream end or the downstream end, thefirst data transmitting device configured to transmit relevantadministration data into the medical fluid residing in the lumen of theconduit; and a first data reader device engaged with the conduit at aposition between the upstream end and the downstream end, the first datareader device configured to receive from the medical fluid in the lumenthe relevant administration data transmitted into the medical fluid bythe first data transmitting device. 2-31. (canceled)